Aldon Smith flies Southwest?
I suppose it could be because he's savvy enough to be thrifty with his money, but he can't be that smart if he's going around DUI and making bomb threats in an airport.
Sometimes Southwest is the only option if you want to go from SoCal to NorCal, especially to a place like San Jose (where I'm assuming he was flying since that's closer to the 49ers facility).
I fly from Burbank to Oakland regularly, and Southwest is the only option.
Also, a flight on Southwest ain't that cheap these days. My flights typically cost about $140 to $180 when I buy months in advance and fly Saturday mornings. (Unless you consider that cheap.)